A consensus structure for membrane transport.
Combined information from biochemical and molecular biological experiments reveals a consistent structural rhythm that underlies the construction of all membrane carriers and perhaps all transport systems. Biochemical work shows that while some carrier proteins function as monomers, others operate as dimers. But despite this variation, all examples can be modelled as having a pair of membrane-embedded domains, each of which contains an array of (about) six transmembrane helical elements. This pattern is best documented among membrane carriers, where the minimal functional unit is known in a reasonable number of cases. Nevertheless, the same conclusion is likely to characterize other solute transporters. These unexpected correlations suggest that all membrane carriers, including those that take part in "energy coupling", have a uniform structural design on which is superimposed a variety of kinetic and biochemical mechanisms.
Maloney
P C
PC
Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD 21205.
D001426:Bacterial Proteins / Q000378:metabolism*; D001693:Biological Transport, Active; D002352:Carrier Proteins / Q000378:metabolism*; D004734:Energy Metabolism; D029968:Escherichia coli Proteins; D005057:Eukaryotic Cells / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D008958:Models, Molecular; D015394:Molecular Structure; D009004:Monosaccharide Transport Proteins; D011387:Prokaryotic Cells / Q000378:metabolism; D011487:Protein Conformation; D013329:Structure-Activity Relationship
D001426:Bacterial Proteins; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; D008565:Membrane Proteins; D009004:Monosaccharide Transport Proteins; C063498:UhpT protein, E coli